Gusseted type ea.gs

ABSTRACT

1. A BAG OF TUBULAR FORM COMPRISING A PLURALITY OF AT LEAST THREE CONTIGUOUS PLIES OF FLEXIBLE SHEET MATERIAL, SAID BAG HAVING A FRONT SURFACE AND AN OPPOSITELY DISPOSED REAR SURFACE ADAPTED TO OVERLAP SAID FRONT SURFACE AT ONE END OF SAID TUBE WHEN SAID BAG IS IN ITS ASSEMBLED CONDITION, SAID BAG BEING LONGITUDINALLY AND REVERSELY CREASED ALONG DIAMETRICALLY OPPOSED PORTIONS TO PROVIDE A PAIR OF OPPOSITELY DISPOSED GUSSETS INTERPOSED BETWEEN SAID FRONT AND REAR SURFACES, EACH OF SAID GUSSETS HAVING AN EXPOSED FRONT PORTION AND AN EXPOSED REAR PORTION WHICH IS STEPPED ABOVE SAID FRONT PORTION AND ADAPTED TO OVERLAP SAID FRONT PORTION WITHIN THE OVERLAPPED AREA OF SAID FRONT AND REAR SURFACES AT SAID END OF THE TUBE WHEN SAID BAG IS IN ITS ASSEMBLED CONDITION, AT LEAST SOME OF THE BAG PLIES BEING STEPPED IN SAID FRONT AND REAR SURFACE PORTIONS TO PROVIDE EXPOSED PORTIONS THEREOF, A HEAT REACTIVE BONDING AGENT IN A DORMANT STATE SUBSTANTIALLY COVERING SAID EXPOSED GUSSET PORTIONS AND FRONT AND REAR SURFACE PORTIONS AT SAID END OF THE TUBE WHEN SAID BAG IS IN ITS ASSEMBLY CONDITION, AND SAID BONDING AGENT BEING REACTIVATABLE TO CLOSE SAID BAG END, THE OPPOSITE END OF SAID TUBE THE REVERSE OF SAID ONE END AND BEING FOLDED OVER AND ADHERED TO A SURFACE OF SAID TUBE BY MEANS OF SAID BONDING AGENT.

Jan. 28, 1975 J. J. GOODRICH Re. 28317 GUSSETED TYPE BAGS 4 Sheets-Sheet l V Original Filed May 26, 1972 Jan. 28, 1975, J J GOODRlCH Re. 28,317

GUSSETBD TYPE BAGS 4 Sheets-Shewt 2 Original Filed May 26, 1972 Jan. 28, 1975 J4 1 GOODRICH RC. 28,317

GUSSETED TYPE BAGS Oflfilhul Fil- May 26, 1972 Jan. 28, 1975 Urigmul w: May 26,

J. J GOODRICH GUssETEru TYPE BAGS United States Patent 28.317 GUSSETED TYPE BAGS John J. Goodrich, Pensacola, Fla., assignor to St. Regis Paper Company, New York, N.Y.

Original No. 3,776,451, dated Dec. 4, I973, Ser. No.

257,253. May 20, 1972., which is a division of application Ser. No. 467.416, June 28, [965, which is a continuation-in-part of application Ser. No. 169,287, Jan. 29, 1962. Application for reissue Mar. 8, 1974, Ser. No.

Int. Cl. 865d 31/02, 33/02 US. Cl. 229--55 6 Claims Matter enclosed in heavy brackets appears In the original patent but forms no part of this reissue specification: matter printed in italics indicates the additions m-'de by sue.

ABSTRACT OF THE DISCLOSURE A bag of tubular form comprising a plurality of contiguous plies of flexible sheet material, said bag having a front surface and an oppositely disposed rear surface adapted to overlap said front surface at one end of said tube when said bog is in its assembled condition. said bag being longitudinally and along diametrically opposed portions to provide a pair of oppositely disposed gussets interposed between said front and rear surfaces, each of said gussets having a front portion and stepped rear portion adapted to overlap said front portion within the overlapped area of said front and rear surfaces at said end of the tube when said bag is in its assembled condition, a bonding agent in a dormant state substantially covering said exposed surfaces at said end of the tube when said bag is in its assembled condition, and said bonding agent being reactivatable to close said bag end, the opposite end of said tube being the reverse of said one end and being folded over and adhered to a surface of said tube by means of said bonding agent, the innermost ply being preferably of a heat scalable material This application is a division of a copending applicahon Ser. No. 467.416, filed June 28, 1965 (now US. Pat. No. 3,687.356)[.] which is in turn a continuatiom m-pari of copending application Ser. No. 169,287, filed Jun, 39, 1962.

The invention pertains to improvements in gusseted bags of the so-called pinch bottom type. Gusseted bags constructed in accordance with the invention may be fabricated from flexible sheet material, such as paper or the like and find wide use in protecting many differ ent types of commodities during transit.

The invention pertains more particularly to a bag of tubular form comprising a plurality of contiguous plies of flexible sheet material wherein the bag has a front surface and an oppositely disposed rear surface which is adapted to overlap the front surface at one end of the tube when the bag is in its assembled condition. The bag l longitudinally and reversely creased along diametrically opposed portions in order to provide a pair of oppositely disposed gussets which are interposed beween the front and rear surfaces. Each of the gussets has a front portion and a stepped rear portion which is adapted to overlap the front portion within the overlap area of the front and rear surfaces at the end of the tube when the bag is in its assembled condition.

The invention has as one of its aims, the provision of a new and improved gusseted type bag which has greatly superior closure strength and bonding charac- 'cl'iSilCS as compared to practices of the prior art: and which. controls contamination and insect infestation,

reversely creased Reissued Jan. 28. I975 The invention provides as another of its aims. a ba closure which is of simple and inexpensive construction and which when completed positively seals the bag mouth against leakage and sifting even though the bugs are roughly handled in transit. Such gusseted bag con struction is accomplished with a minimum of bag material wastage.

Another feature of the invention resides in the provi sion of a new and improved gusseted type bag having a heat scalable inner ply of an impervious character which may be heat sealed without having to penetrate a l of the plies of the bag with heat, and which is also of superior strength characteristics by means of over lapping the inside ply and thereby obtaining a better bond with additional strength. Such a structure is useful for retaining liquids or gases within or without the bag The invention provides as another of its aims, a gusseted type bag of the character aforesaid having a greatly simplified bag which may be simply closed and sealed in the packer's factory without the necessity of applying additional adhesive material and without excessive adhesive flowing over the wrong portions of the package, and which simplifies the handling and filling of the bag by the packer as well as simplifying the open ing procedure for the ultimate consumer As still another feature of the present invention. a new and improved gusseted type bag is provided which has a more pleasing appearance and fewer wrinkles and which can still maintain a satisfactory marketable package even when there is slight deviation in the fold line as well as deviations in the bonding agent application According to one form of the invention the lnnel" most ply of the gusseted type bag is fabricated from a heat sealable material. The rear surface of the inner most ply is cut substantially flush with the stepped rear portion of the other plies and the front surface of the innermost ply is cut substantially flush with the front portion of the other plies at the end of the tube when the bag is in its assembled condition.

The invention may be embodied in bags of single wall or multi-wall construction. As applied to multi-wall bags, further improvements of the invention are obtained by successively stepping the successive plies at the bag ends, and/or by similarly successively stepping the plies in only the gusseted portions of the bag In this way, upon forming the bag closure by folding over the bag end and adherently bonding against One of the bug surfaces, all of the bag plies participate and contribute to the bonding action.

In accordance with a further aspect of the invention. a bonding agent in a dormant state is applied to the surfaces of the gusset portions as well as the front and rear surfaces at the end of the tube when the bag is in its assembled condition. The bonding agent is such that it may be reactivated to close the bag subsequent to a later bag filling operation. Further, in a modified form of the invention the bonding agent may be applied in transverse spaced strips on the face of the steps at the end of the tube. In still another form of the invention the bonding agent is applied adjacent the upper edges of the steps so that portions of the gusset may be ad hered to the rear surface of the tube. This is particularly advantageous since it eliminates the necessity for manually tucking in the gussets or corners of the bag. which would otherwise be required after the filling operation.

As another aspect of the invention the lOl'lgilLldll'ldl width of the rear gusset exposed surfaces may be sub stantially less than the width of the rear wall exposed surface of the front gusset exposed surfaces Still another aspect of the present in ention resides ll the ioitsion oi .i new and improved gusseied type it; l'lLlHflg it free floating polyethylene inside ply fhis P lLlC ii moisture and air impervious inner ply which il expand or contract without encountering ad erse lt'tl\lr)|'l compression torces normally accompanying ttltl -l oiided plies al o ic'CUl'dtl'lg to the present invention a thumb notch nrtv he provided in the outside ply of the front tlildtt tdyaceni the top edge of the rear surface when he 'ClJI stiituce l\ tolded over and adhered to the front siiilticc there has thus been outlined rather broadly the more niportiint features of the invention in order that he detailed description thereof that follows may he better understood, and in order that the present contribution the at that be better appreciated. There are. ol oitrse additional features of the invention that will be described hereinafter and which will form the subject or l t claims appended hereto Those skilled in the art Ill .tpprecilne that the conception upon which this dis equivalent constructions as do not depart from the s irit and scope of the invention. Several embodiments ill the invention have been chosen for purposes of illtis tration and description. and are shown in the accompa trying drawings. forming a part of the specifications. wherein FIG I is a perspective view of a gusseted type pinch bottom bag constructed in accordance with the invention.

FIG 2 is an enlarged perspective view showing de ititoi r .losure structure according to one form of the invention;

FIG 1 is a plan view of a blank of flexible sheet mate rial for fabrication into a multi-ply or multi-wall bag.

FIG 4 is a fragmentary perspective view showing the :losure portion of a gusseted type hag according t a modified form of the invention;

Hi 5 is. a longitudinal sectional view taken substan lill v along the lines indicated at 5-5 in FIG. 4,

Flu a is a fragmentary view showing overlapping .lusurc means of the innermost ply:

FIG. 6 is a fragmentary perspective view showing the closure portion of a gusseted type bag according to the invention after the exposed surfaces have been folded et in bonded condition;

Fti'l is a longitudinal sectional view taken along the line lfldtidlcd -tt 7-7 in FIG. 6 and showing details of the onding etween the exposed surfaces and the face --i the mom wall of the bag,

FIG 8 is a fragmentary perspective view showing a modified form of the gusset structure when the bag "the is in its flattened condition;

Flt; 9 is a fragmentary perspective iew similar to fit] tt but showing the gusset structure after the pack tge has een partially opened;

lt W is a fragmentary elevation showing another tittitiiheit torm of the gusset construction according to he invention FIC i I is a fragmentary elevation illustrating still an other form of closure means according to the in en ion. wherein portions of the gussets are adhered to the teat surface MK I: s a perspective view of a gusseted type hag \hUV-ll'ls! the thumb notch opening means;

l-l( i is a. perspective view similar to FIG [2. but illustrating the operation of the thumb notch opening "team, and

HG i4 is a perspective view ul a modified form of h nvention showing a multi-wall bag construction wherein the bag plies are successively stepped at the ag ends In the embodiment the invention illustrated of in t-'(. t 1 the gusseted type bag is formed lrotn t pin iitli y -it contiguous plies including plies l0, l2 and 14 Fill i of flexible sheet material. such as kraft or other paper Ihe innermost ply may have a thin plastic coiii mg of p lyethylene or the like. applied to one or hUlll surfaces thereof for moisture proofing. The plies lt). IE and H are longitudinally stepped as indicated in FIG 3 so that when the blank is formed into a tubular mem her the )Oll'lltlg of the respective longitudinal edge i each ply will he staggered It is noted that only one end of the ag or tubular structure is shown. however II s understood that the other end of the bag is constructed in a like complementary stepped manner as best \een in FIGS. l and 2, the bag has a tron! all surface l6 and an oppositely disposed rear wall suttiice I8 adapted to overlap or extend above the front \Ul'ftiL'C at one end of the tube when the bag is in its assembled condition. Referring to FIG. 1, the bag is lOl'lgllUdll'lLtll creased along fold lines 20. 22. 24 and 26. and further. the bag is longitudinally and reversely creased diametrically opposed lines 28 and 30, thereby forming a pair of oppositely disposed gussets indicated generally at 32 and 34 which are interposed between the front and rear walls or surfaces 16 and 18.

Referring to FIGS. 4 and 5, the innermost ply desig nated generally at 58 has a front wall exposed surface 60 which extends beyond the other front wall plies and a rear wall exposed surface 62 which extends below the other rear wall plies. Preferably the front surface 60 i substantially flush with the front gusset exposed sur faces 64. and the rear wall exposed surface 62 is flush with the rear gusset surfaces 66. The innermost ply S8 is fabricated from heat seal material. and accordingly. the exposed surfaces thereof may be subiected to heat and thereby sealed without the necessity of the heat passing through as many plies as would be necessary it the inner ply was of the same relative height as the outer plies. Further. the inner ply 58 may be fabricated from many different types of materials porous and non porous. For example, such materials include polyole tines such as polyethylene and polypropylene. polyam ides such as nylon and polyesters such as polyalkylene derivatives of polycarboxylic acids especially polyethylene terephthalite. Further. the inner ply may be fabri cared into a tubular member in a suitable manner such as that disclosed in copending US. Pat. application Se No 430.4l7, filed Feb. 4. I965 (now US. Pat No .399.(]96l If the inner ply 58 IS thermoplastic coated then. as best seen in FIG. 5a. the rear wall 62 of the inner ply 58 may be doubled over upon itself and the front wall surface 60 overlapped thereover in order to form a hci merit. seal between the two thermoplastic surfaces Keterring to FIGS. 8 and 9. there is illustrated a mod med form of gusset construction. In this form a front gusset surface 68 and a rear gusset surface 70 are ill to substantially the same height or flush. and both are disposed within the overlapped area of the rear wall ex posed su face 40 and the front wall exposed surface 46 Further. according to this form of the invention. the top edge of the front and rear gusset exposed surfaces 68 and 70 are serrated or are provided with diamond or round notching as indicated at 72. The first transverse strip of bonding agent 74 is applied across the rear wall exposed surface 40. and a second transverse strip oi bonding agent is applied across the top edge of the gun sets including the serrated edge portion 72, thereby ad hering both the front and back gussets 68 and 70 to the rear wall 40 at the top of the bag. This has the advnn uge ot preventing leakage of packaging material at the uter extremities of the gussets. and also facilitates cl sure of the bag after filling with packaging material since it eliminates the necessity for manually tucking in the corners of the gussets which would otherwise e re quired Reterring to Fl(i. I there is illustrated a modified form of gusset arrangement wherein three strips of pretlppiied bonding agent in a dormant state are applied to he rear wall exposed surface, to the rear gusset ex posed surfaces and to the front gusset exposed surfaces t'C\pCLIllVCly Thai is. one strip of bonding agent 78 is applied transversely of the bag across the rear wall ex posed surface 76; a second strip 80 of bonding agent is applied to the upper edge of the rear gusset exposed \llfflCt 82 so that a portion of the bonding agent appears on the top edge of the rear gusset exposed surface 82 and a portion of the bonding agent appears on the ad acent portion of the rear wall exposed surface 76. thereby bonding the two surfaces together along the line 84 as well as along the line 86; and a third strip 88 of bonding agent is applied along the top edge of the tront gusset exposed surface 90 in an overlapping mannet as seen in FIG. so that the front gusset exposed surface 90 wnded to the rear gusset exposed surface HI. alon inc line 92 and the front gusset surface 90 is also bonded to the rear wall exposed surface 76 along the line 94. As pointed out above, bonding of the ginsets one to the other and to the rear wall serves to prevent leakage of the packaging material at the extremities of gussets and facilitates closure of the bag afte fillirig with packaging material.

Referring next to FIG. ll, there is illustrated a fur= thet modification of the invention. According to this embodiment, the front gusset exposed surface is stepped below the rear gusset exposed surface and the upper edges of both gusset surfaces are provided with a serrated or sawtooth type contoured edge as indicated at 96 and 98, respectively. This construction pro YldCS a longer effective linear edge for providing better bonding characteristics between the front gusset 90 and the rear gusset 82 as well as the rear gusset 82 and the rear wall exposed surface 76.

Referring to FIGS. 12 and 13, there is shown new and improved means for opening a gusseted type bag. A thumb notch 100 is formed in the outermost ply of a multi-ply bag by an interrupted line of slit 102 therein disposed adjacent the top edge of the rear wall 18 when the rear wall is folded over in sealed condition, Since the aforementioned strips of adhesive material are ad tiered to the outermost ply of the front wall 16, the thumb notch 100 tends to rip the outermost ply of the front wall 16 underneath the folded over portion of the back wall [8, and thereby provides a thumb grip to grasp the so-folded over back wall that it can be easily li ted to open the bag as shown in FIG. 13.

Referring to the multi-wall bag constructions, the bag plies may be successively stepped at the bag ends to provide additional adherence on forming the bag clo-= sure. Thus, referring to FIG. 14, the rear wall exposed surface comprises a plurality of plies which may, for ex ample. include three plies including an outside ply 104, a second ply I06 and an inside ply 108. The rear gusset exposed surfaces include an outside or first ply 110, 1 second ply 112 and an inside or third ply 114. The front gusset exposed surfaces include plies 116, 118 and 120 the from Mii'l exposed surface includes a first ply 122. a second ply I24 and a third ply or inside ply 126. It wili be appieciaied that each of the plies in each of the mo posed surfaces has a bonding agent in a dormant state applied thereto at 128, FIG. 14. The bonding agent s "-dntl atfltlfi to permanently close the bag subse= qucrit to a later bag filling operation. In this way, por= uns of all the bag plies in all surfaces including the guss areas. upon forming the bag closure by folding -ve along the fold line 130 and reactivating the bond ing agent, are adherentiy bonded to the bag auriacc,

it will t understood that various changes in the i1:- tuils. materials and arrangements of parts which haviheen herein described and illustrated in order o ex plain the nature of the invention, may be made by t ose skilled in the art within the principle and scope of the invention. as expressed in the appended claims What is claimed is l. A bag of ubular form comprising a plurality ot a least three contiguous plies of flexible sheet material said bag having a front surface and an oppositely i.ll posed rear surface adapted to overlap said fron Surface at one end of said tube when said bag is in its assemhled condition. said bag being longitudinally and reverelt creased along diametrically opposed portions to o vide a pair of oppositely disposed gussets ll'llclpimfi between said front and rear surfaces, each of said gas sets having an exposed front portion and an exposed rear portion which is stepped above said tront portion and adapted to overlap said front portion within i'lr overlapped area of said front and rear surfaces at said end of the tube when said bag is in its assembled condi tion. at least some of the bag plies being stepped in said front and rear surface portions to provide exposed poi tions thereof, a heat reactive bonding agent in a dot mant state substantially covering said exposed gusset portions and front and rear surface portions at said eiio of the tube when said bag is in its assembled condition. and said bonding agent being reactivatable to close saw bag end, the opposite end of said tube being the reverse of said one end and being folded over and adhered to a surface of said tube by means of said bonding agent 2. A bag according to claim 1 having an inner oti composed of a moisture impervious material.

3. A bag according to claim I in which at. leasr the inner surface of the innermost ply of which is prOVliltiO with a moisture resistant surface.

4. A bag according to claim I, the innermost ply i which is comprised of a heat-scalable plastic material 5. A bag according to claim 4 wherein the opposed walls of said innermost ply are heat sealed to one an other at said folded over end of said bag.

6. A bag according to claim 5 wherein said heat sealed and of said innermost ply is freely displaceable with re spect to the remaining plies at said folded over end of salt! bag References Cited T'he following references, cited by the Examiner. are of record in the patented file of this patent or the trlglndl WILLIAM I, PRICE), Primary Examiner S. P. GARBE, Assistant Examiner Us. hi. it R. 6T.

PATENT NU.

DATED lNVtNTORt St me heteby cove;

surface 46.

Still referring to FIGS. transversely extending strips tt !S cem UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 28, 317 January 28, 1975 J. J. Goodrich fled that erior appears in the above-identified patent and that said Letters Patent ted as shown be|0w Column 4, between lines 24 and Z5, insert the following:

portion 36 and a stepped rear The rear portion 38 is adapted to overlap the apped area of the front and rear wall surfaces sed surfaces 44, and a front wall exposed 1 and 2, there is shown a plurality of spaced of a bonding agent in a dormant state. The

bonding agent is a pre-applied type of thermoplastic resin adhesive of any suitable type,

of the exposed surfaces at the end in horizontally, 2, a first strip While such adhesive could be applied to substantially cover all ar wall exposed surface 40, rear gusset exposed of the bag, it is preferable that it be applied transversely disposed, spaced strips. As seen in FIGS. 1 and 48 is applied on the rear wall exposed surface 40 and extends substantially across the width of the bag. A second strip 50 extends across the rear gusset exposed surfaces 42 and of the rear wall exposed surface as at 51 across the front gusset exposed surfaces 44 and Next, a third strip 52 extends portion 53 of the rear wall exposed surface as at 53, and a fourth strip of bonding agent 54 is applied to packaging certain materials,

with, but when packaging othe a very important function.

the front wall exposed surface 46. When the strip of bonding agent 54 may be dispensed r commodities the bonding agent strip 54 serves That is, the latter strip serves to make the bag contamination or insect proof, otherwise there is the possibility that insects may penetrate through the corners of the bag thereby gaining access to the interior thereof.

Moreover, the strip of bonding agent 54 serves as an added measure of protection in the event that the application apparatus of the strips of bonding agent 48, 50 and 52 misfires or skips a spot, the package would preferably across the adjacent portion preferably across the adjacent UNITED STATES PATENT OFFICE Page 2 CERTIFICATE OF CORRECTION Patent No. ,5l'7 Dated January 28, 1975 Inventor(s) J. Goodrich It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

nevertheless be satisfactorily sealed.

As best seen in FIGS. 6 and 7, closure of the package is accomplished by folding the end along the fold crease 56, thus to adhere the bag end to the outer ply of the front surface 16. As seen in FIG. 7, each of the adhesive strips 48, 50, 52 and 54 are in direct contact with the front surface. This is why applicants bag is of substantially superior strength as compared to bags of the prior art.

Normally the bags are shipped to the packers in the condition as shown in FIG. 2 with the bonding medium already applied. The packer opens the top of the bag and inserts a filling spout therein for filling the bag with a desired commodity. Thereafter, the operators tuck-in the gusset portions and fold over the end of the bag along crease line 56, FIG. 2. Normally heat and pressure are applied to reactivate the preapplied bonding agent to thereby permanently close the bag. This may be accomplished by means of hot ressure bars or hot rollers, as desired. Also, with certain types of bonding agents, a hot air blast may be employed to reactivate the bonding agent, or in still other instances the bonding agent may require chemical reactivation.

It will be appreciated that with the aforementioned type of preapplied bonding agent, the packer is not troubled with the problem of applying adhesive to the bag in his plant. This may be particularly desirable when packaging comestibles wherein adhesive may accidently become intermingled with the contents of the package.

Signed and sealed this 27th day of May 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks IM PC1-1050 (00 USCOMM-DC scam-ps9 U 5 GOVERNMENT PDUN'HNG OHICE 9 o Dedication Reissue No. 28,317.JOIm J. Goodrich, Pensacola, Fla. GUSSETED TYPE BAGS. Patent dated Jan. 28, 1975. Dedication filed May 8, 1978, by the assignee, St. Regis Paper Company.

Hereby dedicates t0 the Public the remaining term of said patent.

[Ofiioial Gazette June 2'7, 1.978.] 

